How to Tell If You Have Mold in Your Commercial Building

Mold plays an important role in nature, but that doesn’t mean you want it in your commercial building! Left untreated, mold can threaten the health of building occupants and even damage structural integrity. In this thorough guide, you’ll learn the effects of mold on your health, how to spot mold growth, how to get rid of mold, and tips to prevent it from returning.

Things to Know About Mold in a Commercial Building

Mold can grow virtually anywhere, including outdoors and inside homes and businesses. This microbial growth is particularly problematic for commercial building owners because it can spread to hidden surfaces and impair indoor air quality. This creates liability for the building owner, meaning mold mitigation efforts must occur as soon as possible

Mold and Indoor Air Quality

While some types of mold are more harmful than others, it can be difficult to tell them apart. Therefore, it’s best to remove any mold you find. Failure to act quickly could result in poor indoor air quality, especially if the mold contaminates your HVAC system. When this happens, spores spread every time the air conditioner or heater turns on, potentially affecting every corner of the building.

Prolonged exposure to airborne mold spores can cause flu-like symptoms, even in people who are not particularly sensitive. The health problems to watch out for include:

  • Coughing
  • Itchy throat
  • Sneezing
  • Wheezing or breathing difficulties
  • Runny nose or congestion
  • Skin or eye irritation
  • Headaches
  • Rash
  • Allergic reactions
  • Heightened asthma symptoms

Keep track of when you and your employees experience these symptoms. If they seem worse at work and diminish elsewhere, this could indicate a localized mold problem. Consult your physician if you have any questions or concerns.

Sources & Locations of Mold Growth in Commercial Buildings

Contrary to popular belief, mold doesn’t require standing water to grow. As long as oxygen and a food source are present, high humidity or condensation may be enough for a colony to form. Some common moisture problems that lead to mold growth in commercial buildings include:

  • Roof or plumbing leaks
  • Poor drainage around the property
  • Unvented or poorly vented appliances
  • Lack of air circulation and ventilation

Sometimes, mold growth is readily apparent. Other times, it’s hidden from view but continues to affect indoor air quality. Be aware of these common hiding places for mold in commercial buildings:

  • Behind drywall, wall paneling, and wallpaper
  • Above acoustical ceiling tiles
  • On attic and wall insulation
  • Under carpets and padding
  • On the wall behind furniture that never moves
  • In condensate drain pans and evaporator coils within the HVAC system

Warning Signs of Mold

how to tell if you have mold in a commercial building in Baltimore MD

Health problems related to poor indoor air quality are the first sign of mold in a commercial building. Here are other clues to watch for:

  • Visible mold growth: The easiest way to tell your building has mold is if you can see it. Check out the section below for tips to tell mold from other substances.
  • Lingering musty odors: If specific areas of your building smell persistently damp or musty, odds are mold is hiding nearby.
  • Water damage: Moisture is a key ingredient for mold growth, so water damage is often a catalyst. Look for signs of leaks, such as ceiling stains, warped drywall, cracking or bubbling paint, and peeling wallpaper.
  • History of past flooding: If your property flooded recently, mold might set in if thorough cleaning did not occur within 24 to 48 hours.

How to Tell Mold from Other Substances

Mold can be slimy, fuzzy, or powdery and come in nearly any color. At times, something you think is mold is actually nothing but harmless dust, dirt, mud, or another inorganic material. Follow these guidelines to help you distinguish mold from other substances:

  • Smell: If you notice a musty odor and see what appears to be mold, you can probably trust your senses.
  • Environmental conditions: Mold prefers growing in specific settings. Are you looking at a dry, well-lit area? If so, it’s likely not mold. On the other hand, mold is a major possibility if the environment is damp and low-lit.
  • State of the growing surface: When mold grows on wood or other porous materials, rotting and crumbling can occur.

How to Clean Mold

When dealing with mold, you must first understand the extent of the problem. This determines whether you can handle the cleanup yourself or if you should schedule professional mold removal services.

If the moldy area is 10 square feet or less…

You can probably handle the mold removal yourself. Here’s how to get rid of mold while ensuring your safety and promoting the best results:

  • Wear protective gear: Before you begin, put on a respirator and goggles to limit your exposure to airborne mold. Then, don rubber gloves to protect your hands.
  • Select appropriate cleaning products: A simple solution of warm water and mild detergent is often enough to treat minor mold outbreaks. For more serious contamination, consider using a disinfectant, or a commercial cleaning product specifically made to remove bleach.
  • Scrub the affected area: Spray the moldy surface or dip a stiff-bristled brush directly into your chosen cleaning solution. Scrub hard surfaces thoroughly to remove all visible traces of mold. Allow the area to dry completely.
  • Dispose of porous materials: Items such as carpet, ceiling tiles, upholstery, clothing, and books may not be salvageable. Rather than risk ongoing mold exposure, plan to replace these items.
  • Do not paint or caulk moldy surfaces: These techniques may temporarily hide mold, but growth will continue beneath the paint or caulk, causing more problems in the future.


You should consult a commercial mold remediation specialist in the following situations:

  • Mold growth covers more than 10 square feet.
  • You have asthma, allergies, chronic lung disease, or other respiratory concerns.
  • Mold has damaged an expensive or sentimental item.
  • The building has suffered extensive water damage, so the potential for hidden mold growth is high.
  • You suspect the heating and cooling system may be contaminated with mold.
  • The water and/or mold damage was caused by a storm, sewage backup, or another source of contaminated water.

How to Prevent Mold

The key to long-lasting mold remediation in commercial buildings is to prevent the return of mold once it’s cleaned up. Follow these mold prevention tips to keep future growth at bay:

  • Address leaky plumbing, windows, and roofing as soon as possible.
  • Clean up spills or leaks within 24 to 48 hours.
  • Insulate exposed metal surfaces, such as pipes and ductwork, that may develop condensation.
  • Increase ventilation to introduce cool, dry air from outside into the warm, humid interior.
  • Run exhaust fans to ventilate humid areas, including kitchens and bathrooms.
  • Use fans to increase circulation and prevent stagnant air.
  • Run a dehumidifier to maintain an indoor relative humidity of 60% or lower.
  • Vent moisture-generating appliances, such as clothes dryers, to the exterior.
  • Install indoor air quality products in the HVAC unit to limit the spread of mold spores, including air purification and UV disinfection systems.
  • Install gutters on the building and clean and maintain them regularly.
  • Make sure the soil slopes away from the foundation to help prevent unwanted moisture buildup and leaks.

How to Choose a Mold Remediation Company

If you decide to play it safe and hire a mold removal company, it’s important to make your decision carefully. Follow these tips to ensure you schedule effective, affordable mold removal services:

  • Ask your insurance adjuster to recommend a good mold cleanup service.
  • Inquire about the company’s mold remediation process.
  • Ask for examples of previous work, looking for scenarios similar to yours.
  • Ask if they are IICRC or ACAC certified
  • Pay attention to the level of customer service you receive during your initial interactions with company representatives.

For top-tier commercial mold removal services in Maryland and Washington, DC, turn to BYLT. Our disaster restoration company has years of experience removing and preventing mold in commercial buildings. We follow a quick and effective mold remediation process, so you can get back to business as soon as possible.

If you have questions about potential mold growth in your commercial building, please call us at (410) 770-2900 to schedule an inspection. We’re confident we can handle your mold problem, no matter how severe!